ABSTRACT
The effects of hydroxyethyl starch on the coagulation system have received attention, and safe dosage of high molecular weight hydroxyethyl starch is generally found to be 20 ml.kg-1. Low molecular weight hydroxyethyl starch, HESPANDAR (HES), seems to induce weaker specific effects on blood coagulation than high molecular weight hydroxyethyl starch. The aims of this study are to estimate the maximum safe dosage of HES, and to investigate the etiology for coagulopathy induced by HES. Forty three patients (18 to 75 years old) who were free of bleeding disorders scheduled for abdominal operations received 20, 30, or 40 ml.kg-1 of HES. We measured coagulation parameters of them including platelet, hematocrit, total protein, activated partial thromboplastin time, prothrombin time and Factor 8, and observed the evidence of clinical microbleeding. As the HES was infused, the values of coagulation parameters except Factor 8 changed with blood dilution. Factor 8 decreased more than expected from the values calculated for hemodilution. The evidences of clinical microbleeding were observed when patients had received HES more than 30 ml.kg-1. The decrease of Factor 8 and the observed tendency of clinical microbleeding showed a significant positive relationship (P = 0.0002). We conclude from our results that the maximum safe dosage of HES is about 30 ml.kg-1, and HES may affect blood coagulation by lowering the plasma concentration of Factor 8.
Subject(s)
Blood Coagulation Tests , Hemorrhage/etiology , Hydroxyethyl Starch Derivatives/administration & dosage , Plasma Substitutes/administration & dosage , Abdomen/surgery , Adolescent , Adult , Aged , Factor VIII/metabolism , Female , Humans , Hydroxyethyl Starch Derivatives/adverse effects , Hydroxyethyl Starch Derivatives/chemistry , Male , Molecular Weight , Plasma Substitutes/adverse effectsABSTRACT
The effects of epidural buprenorphine on postoperative respiratory function were studied using respiratory inductive plethysmography (RIP) in two groups of patients [(1) 0.1 mg (2) 0.2 mg] after upper abdominal surgery. Buprenorphine 0.1 mg group showed decreased respiratory rate and increased tidal volume. Decreases in the respiratory rate and the tidal volume were seen in buprenorphine 0.2 mg group and continued for 3-4 hrs after the epidural administration. However, there was no severe respiratory depression in either group. It seems that 0.1 mg of epidural buprenorphine may give a satisfactory postoperative pain relief and less respiratory depression, and RIP is a useful method for the measurement of postoperative respiratory function.
